首先来个docker镜像清理
停掉所有线程：
[root@localhost home]# docker stop $(docker ps -aq)删除所有镜像：
[root@localhost home]# docker rmi -f $(docker images -aq)理解Docker0
三个网络
docker是如何处理容器网络访问的？
上面我们可以看到eth0@if55，这个是docker分配的
[root@localhost home]# ping 172.17.0.2
PING 172.17.0.2 (172.17.0.2) 56(84) bytes of data.
64 bytes from 172.17.0.2: icmp_seq=1 ttl=64 time=0.144 ms
64 bytes from 172.17.0.2: icmp_seq=2 ttl=64 time=0.086 ms
64 bytes from 172.17.0.2: icmp_seq=3 ttl=64 time=0.088 ms
64 bytes from 172.17.0.2: icmp_seq=4 ttl=64 time=0.106 ms
64 bytes from 172.17.0.2: icmp_seq=5 ttl=64 time=0.090 ms我们发现docker是可以ping通的。
原理
- 我们每启动一个docker容器，docker就会给docker容器分配一个ip，我们只要安装了docker，就会有一个网卡docker0桥接模式，使用的技术是evth-pair技术。
- 再启动一个容器测试，我们发现又多了一对网卡。
我们发现这个容器带来的网卡，都是一对一对的
evth-pair 就是一对的虚拟设备接口，他们都是成对出现的，一段连着协议，一段彼此相连
正因为有这个特性，evth-pair充当一个桥梁，连接各种虚拟网络设备的。
我们测试一下tomcat01和tomcat02是否可以ping通
新建一个tomcat02
[root@localhost home]# docker run -d -P --name tomcat02 tomcat:9.0
1c26376153b5720b49292e3aa8579407cd6fc1553350737e58aa0f10761e79a5
[root@localhost home]#
[root@localhost home]#
[root@localhost home]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
1c26376153b5 tomcat:9.0 "catalina.sh run" 5 seconds ago Up 3 seconds 0.0.0.0:49155->8080/tcp, :::49155->8080/tcp tomcat02
6c545fef8cc9 tomcat:9.0 "catalina.sh run" 14 minutes ago Up 14 minutes 0.0.0.0:49154->8080/tcp, :::49154->8080/tcp tomcat01
[root@localhost home]# docker exec -it tomcat01 ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
54: eth0@if55: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default
link/ether 02:42:ac:11:00:02 brd ff:ff:ff:ff:ff:ff link-netnsid 0
inet 172.17.0.2/16 brd 172.17.255.255 scope global eth0
valid_lft forever preferred_lft forever
[root@localhost home]# docker exec -it tomcat02 ping 172.17.0.2
PING 172.17.0.2 (172.17.0.2) 56(84) bytes of data.
64 bytes from 172.17.0.2: icmp_seq=1 ttl=64 time=0.236 ms
64 bytes from 172.17.0.2: icmp_seq=2 ttl=64 time=0.088 ms
64 bytes from 172.17.0.2: icmp_seq=3 ttl=64 time=0.095 ms
^C
--- 172.17.0.2 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 5ms
rtt min/avg/max/mdev = 0.088/0.139/0.236/0.069 ms
[root@localhost home]# 我们可以看到tomcat02是可以ping通tomcat01的，可以说他们之间是可以相互ping通的。
docker使用的是Linux桥接，宿主机中是一个Docker容器的桥接。
Docker中的所有的网络接口都是虚拟的，虚拟的转发效率高，只要删除容器，对应的网桥也会删除。
容器互联--Link
首先我们来看一段代码
[root@localhost home]# docker exec -it tomcat02 ping tomcat01
tomcat02 ping tomcat01是ping不通的
引用下方命令，新建tomcat03，使用--link连接tomcat02
[root@localhost home]# docker run -d -P --name tomcat03 --link tomcat02 tomcat:9.0
然后我们再tomcat02和tomcat03之间互相ping一下
[root@localhost home]# docker exec -it tomcat02 ping tomcat03
ping: tomcat03: Name or service not known
[root@localhost home]# docker exec -it tomcat03 ping tomcat02
PING tomcat02 (172.17.0.3) 56(84) bytes of data.
64 bytes from tomcat02 (172.17.0.3): icmp_seq=1 ttl=64 time=0.148 ms
64 bytes from tomcat02 (172.17.0.3): icmp_seq=2 ttl=64 time=0.081 ms
^C
--- tomcat02 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 3ms
rtt min/avg/max/mdev = 0.081/0.114/0.148/0.035 ms
[root@localhost home]# 我们发现2 ping 3 不行 但是3 ping 2 却是可以的
如果想要2连3，那么需要在2这里配置3的
现在我们不是这么玩了。
自定义网络
查看所有的Docker网络
[root@localhost home]# docker network ls
NETWORK ID NAME DRIVER SCOPE
870e7b5932d7 bridge bridge local
b849afd2252a host host local
a018dbb14fc5 none null local网络模式：
bridge:桥接docker(默认)
none：不配置网络
host：和宿主机共享网络
container：容器网络连通！(用的少，局限很大)
测试
我们之前在创建网络的时候，docker会给我们默认的网络配置 --net
[root@localhost home]# docker run -d -P --name tomcat01 --net bridge tomcat:9.0
docker 默认指定的网络就是bridge（--net bridge）
所以理论上我们可以不用docker默认的网络，用自己定义的网路
[root@localhost home]# docker network --help
Usage: docker network COMMAND
Manage networks
Commands:
connect Connect a container to a network
create Create a network #可以创建网络
disconnect Disconnect a container from a network
inspect Display detailed information on one or more networks
ls List networks
prune Remove all unused networks
rm Remove one or more networks
Run 'docker network COMMAND --help' for more information on a command.创建自定义网络
[root@localhost ~]# docker network create --driver bridge --subnet 192.168.0.0/16 --gateway 192.168.0.1 mynet
51276ec9ede3d8e0b428f96dbfe6b0cdb6ed8ef8f3ec6fcc8cd40e08390360e4
[root@localhost ~]# [root@localhost ~]# docker network create --driver bridge --subnet 192.168.0.0/16 --gateway 改命令中
--driver bridge
--subnet 192.168.0.0/16 表示我自己定义的网路，16位子网
--gateway 后面显示我的网关
将容器发布到自己创建的网络当中
[root@localhost ~]# docker run -d -P --name tomcat-net-01 --net mynet tomcat:9.0
87caa4dcc10d9a40c796c143132113d63f74ee744c5b4605d799f1242b475895
[root@localhost ~]# docker run -d -P --name tomcat-net-02 --net mynet tomcat:9.0
2a748aa939b4704debd95de41d7778d7c2a480b8a41f36a8fc0c24c420be99ef
[root@localhost ~]# 我们创建两个容器，配置我们自己创建的网络。
同过docker网络查看我们两个容器的配置信息
[root@localhost ~]# docker network ls
NETWORK ID NAME DRIVER SCOPE
870e7b5932d7 bridge bridge local
b849afd2252a host host local
51276ec9ede3 mynet bridge local
a018dbb14fc5 none null local
[root@localhost ~]# docker network inspect 51276ec9ede3
[
{
"Name": "mynet",
"Id": "51276ec9ede3d8e0b428f96dbfe6b0cdb6ed8ef8f3ec6fcc8cd40e08390360e4",
"Created": "2021-08-02T14:11:46.235947859+08:00",
"Scope": "local",
"Driver": "bridge",
"EnableIPv6": false,
"IPAM": {
"Driver": "default",
"Options": {},
"Config": [
{
"Subnet": "192.168.0.0/16",
"Gateway": "192.168.0.1"
}
]
},
"Internal": false,
"Attachable": false,
"Ingress": false,
"ConfigFrom": {
"Network": ""
},
"ConfigOnly": false,
"Containers": {
"2a748aa939b4704debd95de41d7778d7c2a480b8a41f36a8fc0c24c420be99ef": {
"Name": "tomcat-net-02",
"EndpointID": "0caa924913d2c7140fb3ab6f756a1df2174810ce79a729d084ec19d7dd800f75",
"MacAddress": "02:42:c0:a8:00:03",
"IPv4Address": "192.168.0.3/16",
"IPv6Address": ""
},
"87caa4dcc10d9a40c796c143132113d63f74ee744c5b4605d799f1242b475895": {
"Name": "tomcat-net-01",
"EndpointID": "42d7ada04da6b9b548057c2f1d55de89960eca4f790250e0fb317b1418150fe4",
"MacAddress": "02:42:c0:a8:00:02",
"IPv4Address": "192.168.0.2/16",
"IPv6Address": ""
}
},
"Options": {},
"Labels": {}
}
]现在我们来测试一下：
他们两个之间的互相访问成功
[root@localhost ~]# docker exec -it tomcat-net-02 ping tomcat-net-01
PING tomcat-net-01 (192.168.0.2) 56(84) bytes of data.
64 bytes from tomcat-net-01.mynet (192.168.0.2): icmp_seq=1 ttl=64 time=0.178 ms
64 bytes from tomcat-net-01.mynet (192.168.0.2): icmp_seq=2 ttl=64 time=0.069 ms
64 bytes from tomcat-net-01.mynet (192.168.0.2): icmp_seq=3 ttl=64 time=0.082 ms
^C
--- tomcat-net-01 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 4ms
rtt min/avg/max/mdev = 0.069/0.109/0.178/0.050 ms
[root@localhost ~]# 我们自定义的网络docker都已经帮我们维护好了对应的关系
好处：
redis-不同的集群使用不同的网络，保证集群是安全和健康
mysql-不同的集群使用不同的网络，保证集群是安全和健康
网路联通
我们使用tomcat02 访问tomcat-02-net
[root@localhost ~]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
2a748aa939b4 tomcat:9.0 "catalina.sh run" 5 minutes ago Up 5 minutes 0.0.0.0:49158->8080/tcp, :::49158->8080/tcp tomcat-net-02
87caa4dcc10d tomcat:9.0 "catalina.sh run" 6 minutes ago Up 6 minutes 0.0.0.0:49157->8080/tcp, :::49157->8080/tcp tomcat-net-01
c0b80e6be2cb tomcat:9.0 "catalina.sh run" 3 hours ago Up 3 hours 0.0.0.0:49156->8080/tcp, :::49156->8080/tcp tomcat03
1c26376153b5 tomcat:9.0 "catalina.sh run" 3 hours ago Up 3 hours 0.0.0.0:49155->8080/tcp, :::49155->8080/tcp tomcat02
6c545fef8cc9 tomcat:9.0 "catalina.sh run" 4 hours ago Up 4 hours 0.0.0.0:49154->8080/tcp, :::49154->8080/tcp tomcat01
[root@localhost ~]# docker exec -it tomcat-net-02 ping tomcat02
ping: tomcat02: Name or service not known
[root@localhost ~]# 可以看到的是tomcat02 访问tomcat-02-net是访问不通的
我们查看docker network --help 看有没有解决方法
[root@localhost ~]# docker network --help
Usage: docker network COMMAND
Manage networks
Commands:
connect Connect a container to a network #docker给出的方法
create Create a network
disconnect Disconnect a container from a network
inspect Display detailed information on one or more networks
ls List networks
prune Remove all unused networks
rm Remove one or more networks
Run 'docker network COM测试打通tomcat01到tomcat-01-net
[root@localhost ~]# docker network connect mynet tomcat01
[root@localhost ~]# docker exec -it tomcat-net-01 ping tomcat01
PING tomcat01 (192.168.0.4) 56(84) bytes of data.
64 bytes from tomcat01.mynet (192.168.0.4): icmp_seq=1 ttl=64 time=0.135 ms
64 bytes from tomcat01.mynet (192.168.0.4): icmp_seq=2 ttl=64 time=0.087 ms
64 bytes from tomcat01.mynet (192.168.0.4): icmp_seq=3 ttl=64 time=0.079 ms
64 bytes from tomcat01.mynet (192.168.0.4): icmp_seq=4 ttl=64 time=0.061 ms
^C
--- tomcat01 ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 6ms
rtt min/avg/max/mdev = 0.061/0.090/0.135/0.028 ms我们再来看看mynet里面的信息
[root@localhost ~]# docker network inspect mynet
[
{
"Name": "mynet",
"Id": "51276ec9ede3d8e0b428f96dbfe6b0cdb6ed8ef8f3ec6fcc8cd40e08390360e4",
"Created": "2021-08-02T14:11:46.235947859+08:00",
"Scope": "local",
"Driver": "bridge",
"EnableIPv6": false,
"IPAM": {
"Driver": "default",
"Options": {},
"Config": [
{
"Subnet": "192.168.0.0/16",
"Gateway": "192.168.0.1"
}
]
},
"Internal": false,
"Attachable": false,
"Ingress": false,
"ConfigFrom": {
"Network": ""
},
"ConfigOnly": false,
"Containers": {
"2a748aa939b4704debd95de41d7778d7c2a480b8a41f36a8fc0c24c420be99ef": {
"Name": "tomcat-net-02",
"EndpointID": "0caa924913d2c7140fb3ab6f756a1df2174810ce79a729d084ec19d7dd800f75",
"MacAddress": "02:42:c0:a8:00:03",
"IPv4Address": "192.168.0.3/16",
"IPv6Address": ""
},
------------------"重点"----------------------
"6c545fef8cc9ccebbad800db7bdd2388cea6ec0ad1eb31be1033c6b96d99191a": {
"Name": "tomcat01",
"EndpointID": "b055a1f9cf792bb970b11ef63e66f18d093e0e234baa19ab688de14dc42ac288",
"MacAddress": "02:42:c0:a8:00:04",
"IPv4Address": "192.168.0.4/16",
"IPv6Address": ""
},
"87caa4dcc10d9a40c796c143132113d63f74ee744c5b4605d799f1242b475895": {
"Name": "tomcat-net-01",
"EndpointID": "42d7ada04da6b9b548057c2f1d55de89960eca4f790250e0fb317b1418150fe4",
"MacAddress": "02:42:c0:a8:00:02",
"IPv4Address": "192.168.0.2/16",
"IPv6Address": ""
}
},
"Options": {},
"Labels": {}
}
]联通之后，就是把tomcat01加入到mynet里面，实际上就是一个容器，两个地址
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